You can add a PV manually to tie to some resource that was already created, but you don't get the bi-directional link. I'm not sure I'd even want K8s adding PV's for all volumes (maybe filtering by labels/tags would be ok).

This is approaching Terraform levels of complexity though. Unless you mean that cloud providers should do that when you create a volume, in which case I understand where you are coming from and well, they could do that. Although I'd much have them exposing a native K8s interface to take care of this PV and PVC for me and not showing me the underlying volumes at all.